Field of the Invention
The present invention relates in general to the field of information handling system display device communication, and more particularly to a configurable information handling system display communication link.
Description of the Related Art
As the value and use of information continues to increase, individuals and businesses seek additional ways to process and store information. One option available to users is information handling systems. An information handling system generally processes, compiles, stores, and/or communicates information or data for business, personal, or other purposes thereby allowing users to take advantage of the value of the information. Because technology and information handling needs and requirements vary between different users or applications, information handling systems may also vary regarding what information is handled, how the information is handled, how much information is processed, stored, or communicated, and how quickly and efficiently the information may be processed, stored, or communicated. The variations in information handling systems allow for information handling systems to be general or configured for a specific user or specific use such as financial transaction processing, airline reservations, enterprise data storage, or global communications. In addition, information handling systems may include a variety of hardware and software components that may be configured to process, store, and communicate information and may include one or more computer systems, data storage systems, and networking systems.
Often, information handling systems process information with the goal of presenting results of the processing at a display for an end user. Displays typically use a large number of pixels, each of which presents a color so that the totality of pixels presents an image. For example, a high definition display has a native resolution of at least 1920×1080 pixels. Generally, once an information handling system has generated information for presentation at a display, a graphics processor of the information handling system creates pixel values from the information that create the visual image at the display. The graphics system communicates the pixel values to a timing controller, which sets the pixel values to present the image with each pixel having a color defined by its pixel value. Static images, such as word processing documents, do not change pixel values very often so that the same values are repeatedly refreshed at the display. Dynamic images, such as movies, can change pixel values quite rapidly as images move on the display. In order to show moving images with clarity, large amounts of data can be sent from an information handling system to a display. In order to accommodate communication of pixel values to a display, the industry has developed a variety of standards for sending pixel values as digital information, including the Digital Visual Interface (DVI), High-Definition Multi-Media Interface (HDMI®) and DISPLAYPORT standards.
The DISPLAYPORT standard defines a cable and interface that communicate pixel values from a graphics system to a display on four unidirectional data serial links and also includes a bi-directional auxiliary link that communicates management information between the graphics system and display. For example, the auxiliary link allows the display to provide an identifier to the graphics system for automated setup. The DISPLAYPORT standard calls for a relatively low bandwidth across the auxiliary link, however, one alternative to the standard auxiliary link that provides increased bandwidth on the auxiliary link is to use a USB link as the auxiliary link. Having additional bandwidth allows communication of additional information between the display and graphics system, such as information associated with peripherals coupled to the display. For example, a mouse, video camera, memory card reader or speakers can interface with a port or wireless transceiver at the display and then use the USB auxiliary link to communicate with the information handling system through a DISPLAYPORT cable. The extra bandwidth provided by the USB serial link reduces the number of separate cables that are needed to interface the display with its peripherals. If even more bandwidth is needed, one alternative approach is to support bi-directional communication with the unidirectional data serial links that normally communicate pixel values. DISPLAYPORT can generally support the resolution of high definition displays with just two unidirectional data serial links so that the two remaining data serial links can be “borrowed” to support communication of other data, such as with the PCIe or USB protocols. However, “borrowing” two data serial links to establish one PCIe link provides a limited solution that may not efficiently use available bandwidth. As display resolution increases, “borrowing” display data links to create a PCIe link will impact the presentation of images at the display due to restricted bandwidth through the two data links.